JP2013145067A - Biomass combustion burner and biomass combustion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biomass combustion burner capable of stable combustion by preventing reduction of ignitability of biomass fuel during combustion.SOLUTION: A biomass combustion burner 1 includes a liquid fuel nozzle 2 provided on a central shaft, a biomass fuel nozzle 3 for jetting biomass fuel and carrier gas at an outer circumference of the liquid fuel nozzle 2, a fuel concentrator 9 provided on an outer circumference of the liquid fuel nozzle 2, a flame stabilizer 13 provided at a front end of the biomass fuel nozzle 3, and a combustion gas nozzle 5 provided on an outer circumference of the biomass fuel nozzle 3. A solid fuel nozzle 4 is provided on the outer circumference of the biomass fuel nozzle 3 and on the inner circumference of the combustion gas nozzle 5 and conveying particles of solid fuel, and a particle jetting port 10 from the solid fuel nozzle 4 into the biomass fuel nozzle 3 is provided between the fuel concentrator 9 and the flame stabilizer 13 and in the vicinity of the flame stabilizer 13. By particles from the jetting port 10, particles concentrated in the vicinity of the flame stabilizer 13 of the biomass fuel nozzle 3 inner wall are ignited, enabling stable combustion.

Description

  The present invention relates to a biomass combustion burner and a biomass combustion apparatus, and more particularly to a burner apparatus that enhances ignitability in the vicinity of the outlet of the burner.

  Due to the problem of global warming caused by carbon dioxide in recent years, biomass fuel called carbon neutral has attracted attention. Biomass is an organic matter produced by living organisms through photosynthesis, and carbon dioxide released by burning biomass is carbon dioxide absorbed from the atmosphere by photosynthesis during the growth of the organism. Thus, biomass is a neutral fuel that does not increase atmospheric carbon dioxide during the life cycle of the organism.

  Therefore, in order to reduce carbon dioxide emissions from thermal power plants, the development of biomass fired boilers that use biomass fuel instead of fossil fuel, or biomass fuel co-fired boilers that replace part of fossil fuel with biomass fuel is underway. It has been.

  Compared with fossil fuels, for example, coal, biomass fuels differ greatly in properties such as density, volatile content, moisture content, and ratio of contained elements.Therefore, biomass fuel is used in the same burner as fossil fuels such as coal. When burned, the combustion state of fossil fuel is greatly different from that when burning. Therefore, development of a biomass burning burner for burning biomass fuel is being promoted.

The following patent documents 1-4 are mentioned as an example of a biomass combustion burner.
In Patent Document 1, at least four cylindrical members having different diameters are combined concentrically (coaxially), auxiliary fuel for ignition is supplied from the innermost side, air for auxiliary fuel combustion, biomass fuel, A multi-tube biomass combustion burner is disclosed that burns biomass fuel by supplying biomass fuel combustion air.

  Patent Document 2 discloses a mixed combustion burner that ejects pulverized wood from a wood ejection nozzle in the center of the burner and ejects and burns pulverized coal from a coal ejection nozzle provided on the outer periphery of the wood ejection nozzle.

Patent Document 3 discloses a burner in which a flame holder provided at the tip of a central nozzle that supplies biomass fuel has an enlarged structure, or a dispersing device or the like is provided in the central nozzle.
Patent Document 4 discloses a burner in which a biomass fuel injection nozzle is provided on the outer peripheral side of a coal fuel injection nozzle on the center side, and a flame holding plate is provided at the tip of the biomass fuel injection nozzle.

JP 2011-12836 A JP 2007-101083 A JP 2005-291534 A JP 2003-222310 A

  According to the configuration described in Patent Document 1, a multi-tube biomass combustion burner can be realized with a simple structure. Moreover, according to the structure of patent document 2, the combustion temperature is stabilized because the pulverized coal ejected from a coal ejection nozzle wraps the pulverized wood ejected from a wood ejection nozzle. Further, according to the configuration described in Patent Document 3, a stagnation region of biomass fuel is formed inside the furnace of the flame holder to achieve stable combustion. According to the configuration described in Patent Document 4, the vortex is formed by the flame holding plate provided at the tip of the biomass fuel injection nozzle to stabilize the ignition.

Here, in order to burn the biomass fuel, for example, it is necessary to supply to the burner biomass fuel that has been pulverized into fine particles and finely powdered like coal, which is the same solid fuel. However, since the main component of biomass fuel is fiber such as cellulose, it is difficult to pulverize compared to coal.
Taking a coal fired boiler as an example, the particle diameter of coal particles suitable for burning is about 70% to 90% in a 200 mesh pass (particle ratio of a size of 75 μm or less).

  On the other hand, when the biomass fuel is pulverized by a fine pulverizer under the same load as coal becomes 70% to 90% in a 200 mesh pass, the biomass fuel remains at a few percent in the 200 mesh pass. Furthermore, some of the particles have a maximum size of several millimeters, and the particle size of the pulverized biomass fuel is significantly larger than that of coal. In order to reduce the particle size of the biomass fuel, the load on the pulverizer must be increased, which increases power consumption. However, it is practically difficult to pulverize biomass fuel into fine particles similar to coal due to the limitation of pulverization efficiency and the upper limit of power.

  When solid fuel is burned with a burner, first, fine particles of several tens of μm or less are ignited, and fuel particles having a larger particle diameter are burned by the propagation of a flame starting from the fine particles. Therefore, the presence of fine particles of several tens of μm or less is indispensable for stable ignition and stable combustion of solid fuel. However, in the case of biomass fuel in which the proportion of fine particles contained in the pulverized fuel particles is much lower than that of coal, Since the ignitability of the is reduced, stable combustion in the burner was difficult.

In the configuration described in Patent Document 1, although the structure of the burner is simple, stable combustion is difficult unless the strength of swirls (vortices) of primary air or secondary air is changed.
In the configuration described in Patent Document 2, the combustion temperature is stabilized to some extent by wrapping pulverized wood with pulverized coal, but a sufficient amount of pulverized coal is necessary to wrap. Moreover, since the effect will be halved if there is much quantity of pulverized wood, it is necessary to also increase the quantity of pulverized coal. Furthermore, in order to finely pulverize wood, the load of the fine pulverizer must be increased as described above, and the problem of power consumption remains.

  Further, in the configurations described in Patent Document 3 and Patent Document 4, even if a certain amount of stable combustion is possible with a flame holder (flame holding plate), problems such as a decrease in ignitability remain when the biomass fuel particle size is large. . Moreover, since it takes power to finely pulverize the biomass fuel, the biomass fuel is only used as a secondary fuel, and it can be said that the effective use of the biomass fuel is still insufficient.

  The subject of this invention is providing the biomass combustion apparatus provided with this biomass combustion burner which prevents the fall of the ignitability at the time of combustion of biomass fuel, and can perform the stable combustion in a burner.

The above-described problems of the present invention can be solved by the following means.
The invention according to claim 1 is a liquid fuel nozzle provided on a central axis, a biomass fuel nozzle provided on an outer periphery of the liquid fuel nozzle for conveying and ejecting biomass fuel and a carrier gas, and an outer periphery of the liquid fuel nozzle. A fuel concentrator that narrows the flow path of the fuel in the biomass fuel nozzle toward the inner wall side of the biomass fuel nozzle, a flame holder provided on the inner wall of the tip of the biomass fuel nozzle, and an outer periphery of the biomass fuel nozzle A biomass combustion burner provided with a combustion gas nozzle for ejecting a fuel combustion gas, wherein the solid fuel particles are transported to the outer periphery of the biomass fuel nozzle and to the inner periphery of the combustion gas nozzle; A solid fuel nozzle that is jetted to the nozzle, and a jet port of the solid fuel transfer nozzle is provided between the fuel concentrator and the flame holder and in the vicinity of the flame holder. A biomass combustion burner provided in the biomass fuel nozzle wall.

  A second aspect of the present invention is the biomass combustion burner according to the first aspect, wherein the solid fuel is a semi-carbonized biomass fuel.

  According to a third aspect of the present invention, there is provided the biomass combustion burner according to the first aspect, wherein the solid fuel particles are pulverized coal, and a solid fuel pulverizer for pulverizing the solid fuel supplied to the solid fuel nozzle into particles. It is the provided biomass combustion apparatus.

  The invention according to claim 4 is a biomass combustion apparatus provided with the biomass combustion burner according to claim 2 and a solid fuel reservoir for storing particles of the semi-carbonized biomass fuel supplied to the solid fuel nozzle. is there.

(Function)
When solid combustion is performed with a burner, first, fine particles of several tens of μm or less are ignited, and the propagation of a flame starting from the fine particles causes combustion of fuel particles having a larger particle diameter. Therefore, the presence of fine particles of several tens of μm or less is indispensable for stable ignition and stable combustion of solid fuel, but in the case of biomass fuel in which the proportion of fine particles contained in the pulverized fuel particles is much lower than that of coal, Since the ignitability of the is reduced, stable combustion in the burner was difficult.

According to the present invention, the biomass fuel is used as the main fuel, the solid fuel is used as the auxiliary fuel, and the solid fuel particles are supplied into the biomass fuel nozzle from the jet port of the solid fuel nozzle. The proportion of the fine particles can be increased.
For example, solid fuel particles of the order of several tens of micrometers are used as the solid fuel particles. Specifically, the solid fuel may be adjusted to 70% to 90% with a particle ratio of a size of 75 μm or less. Further, the biomass fuel only needs to be roughly pulverized (several millimeters, for example, 2 mm or less).

  The concentrator in the biomass fuel nozzle narrows the transfer channel to the inner wall side of the biomass fuel nozzle, so that the biomass fuel flows from the center of the burner to the outside and the biomass fuel concentration along the inner wall in the radial direction of the biomass fuel nozzle increases. . Since the solid fuel particles are supplied from the outer periphery of the biomass fuel nozzle to the region where the biomass fuel concentration is high, the solid fuel particles efficiently contact and mix with the biomass fuel. In order to form a solid-gas two-phase flow along the inner wall of the biomass fuel nozzle in the radial direction, the concentration of fine particles (this fine particle is both fine particles of biomass fuel and fine particles of solid fuel) increased, The ignitability of fuel at the furnace opening is improved. In addition, since a flame holder is installed on the outlet inner wall of the biomass fuel nozzle, when the solid fuel particles are supplied near the flame holder and hit the flame holder, the particle velocity decreases, and the flame holder is near the flame holder. Particles are concentrated. Therefore, stable ignition of the fuel becomes possible by igniting these particles.

  That is, according to the first aspect of the present invention, the solid fuel particles are ejected from the solid fuel nozzle into the biomass fuel nozzle in the region where the biomass fuel concentration is high and mixed with the biomass fuel. Biomass fuel particles with a larger particle size are burned by the propagation. Therefore, the biomass fuel and the solid fuel particles are efficiently contacted and mixed so that the ignitability at the time of combustion does not decrease even with a biomass fuel having a relatively large particle size and a small proportion of fine particles. Moreover, since contact and mixing of biomass fuel and solid fuel are performed in the vicinity of the flame holder, ignition is performed in the vicinity of the flame holder. Therefore, stable ignition of fuel becomes possible.

  Moreover, when the biomass fuel is semi-carbonized, thermal decomposition of the fiber in the biomass fuel occurs, and the biomass fuel is easily pulverized. Furthermore, since biomass fuel originally contains a large amount of volatile components, it has high ignitability and is suitable as a fuel. The semi-carbonized biomass fuel is a fuel in which the biomass fuel is heat-treated at about 200 ° C. to 300 ° C. in a reducing atmosphere and the water content is reduced to several percent or less while leaving the volatile components contained in the biomass fuel. . Carbonized fuel is not only moisture but also volatile components removed from biomass fuel, and is distinguished from semi-carbonized biomass fuel.

  Therefore, according to the invention described in claim 2, in addition to the action of the invention described in claim 1, the use of biomass fuel that has been semi-carbonized as a solid fuel further improves ignitability. It becomes. In addition, when the fuel is finely pulverized, the power is reduced as compared with the untreated biomass fuel.

  And according to invention of Claim 3, in addition to the effect | action of the invention of said Claim 1, when using pulverized coal as a solid fuel, the pulverizer originally provided in the normal pulverized coal combustion apparatus By using the pulverized coal fuel can be smoothly supplied to the solid fuel nozzle, and the fuel supply system can be prevented from becoming complicated.

According to the invention described in claim 4, in addition to the operation of the invention described in claim 2, the semi-carbonized biomass fuel is smoothly supplied to the solid fuel nozzle by providing a reservoir of the semi-carbonized biomass fuel. it can. If the solid fuel is pulverized coal, the fine powder crushed by the pulverizer is supplied as it is without storing, but the semi-carbonized biomass fuel is the biomass from which moisture has been removed. The water | moisture content of this is absorbed and a grindability will fall. In addition, a new semi-carbonized biomass fuel grinder is costly.
Therefore, when using semi-carbonized biomass fuel as the solid fuel, it is desirable to pulverize and store before absorbing moisture in the atmosphere.

ADVANTAGE OF THE INVENTION According to this invention, the biomass combustion burner which can prevent the fall of the ignitability at the time of combustion of biomass fuel and can perform stable ignition can be provided. Specifically, it has the following effects.
According to the first aspect of the present invention, combustion of biomass fuel particles is promoted by ejecting solid fuel particles from the solid fuel nozzle into the biomass fuel nozzle. Therefore, even if a biomass fuel having a relatively large particle size and a small proportion of fine particles is used, a decrease in ignitability during combustion is prevented, and stable combustion in the burner is possible. Further, since the biomass fuel and the solid fuel particles efficiently contact and mix, the ignitability can be improved even if the flow rate of the solid fuel particles is reduced as much as possible.

  According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, by using a biomass fuel that has been semi-carbonized as a solid fuel, it does not require much labor for pulverization and is ignitable. Can provide an excellent burner. Furthermore, it can also be used as a burner for biomass fuel, enabling more effective use of biomass fuel.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1, by using an existing pulverizer for pulverized coal in the pulverized coal combustion device, the pulverized coal fuel is supplied to the solid fuel nozzle. Can be supplied smoothly, so it can be constructed as a biomass combustion system.

  According to the invention described in claim 4, in addition to the effect of the invention described in claim 2, the semi-carbonized biomass fuel can be smoothly supplied to the solid fuel nozzle by providing the reservoir for the semi-carbonized biomass fuel. When a new semi-carbonized biomass fuel pulverizer is provided, costs are increased and moisture in the atmosphere is absorbed before pulverization, resulting in a decrease in pulverization properties. However, such a problem does not occur. Moreover, by using the semi-carbonized biomass fuel as the solid fuel, the biomass fuel can be used effectively and can be constructed as a biomass-only firing system.

It is sectional drawing which shows the structure of the burner part of one Embodiment of this invention. It is an enlarged view of the front-end | tip part of the solid fuel nozzle of the burner of FIG. It is the figure (figure seen from the furnace side to the burner direction) which showed the structure of the flame holder of the burner of FIG. It is a systematic diagram of the biomass combustion apparatus provided with the burner of FIG. It is a systematic diagram of the biomass combustion apparatus provided with the burner of FIG.

  Examples of the present invention will be described below.

  In FIG. 1, the block diagram of the biomass combustion burner which concerns on the Example of this invention is shown. In this embodiment, the liquid fuel nozzle 2 provided along the central axis C (FIG. 2) of the biomass combustion burner 1 and the outer periphery of the liquid fuel nozzle 2 are used to carry the biomass fuel by the biomass fuel carrying gas (primary air). The biomass fuel nozzle 3 to be supplied to the furnace 12, the flame holder 13 provided on the inner wall of the tip portion of the biomass fuel nozzle 3, and the biomass fuel nozzle 3 are provided on the outer periphery of the biomass fuel nozzle 3. A solid fuel nozzle 4 provided with an outlet 10 for jetting to the nozzle 3, a combustion gas jet nozzle (for secondary air) 5 provided on the outer periphery of the solid fuel nozzle 4 and jetting a combustion gas to the furnace 12, It comprises a concentrator 9 for fuel concentration in the biomass fuel nozzle 3 and the like. Since the concentrator 9 is provided on the outer periphery of the liquid fuel nozzle 2, the concentrator 9 has an action of narrowing the fuel conveyance path in the biomass fuel nozzle 3 toward the inner wall side of the biomass fuel nozzle 3.

  Furthermore, an air register 6 for forming a swirling flow at the burner outlet on the outer periphery of the combustion gas jet nozzle 5, a combustion gas jet nozzle (for tertiary air) 7 for jetting the combustion gas to the furnace 12, and biomass fuel A venturi 8 for reducing the flow path in the nozzle 3 may be provided.

FIG. 2 shows the structure of the solid fuel nozzle 4. FIG. 2 shows an enlarged view of the tip portion of the solid fuel nozzle 3 of the biomass combustion burner 1 of FIG.
The tip of the solid fuel nozzle 4 is connected to a hole (jet port) 10 provided on the wall surface of the biomass fuel nozzle 3. The solid fuel particles in the solid fuel nozzle 4 pass through the solid fuel nozzle 4 together with the carrier gas into the biomass fuel nozzle 3.

  In this embodiment, the biomass fuel is used as the main fuel, and the solid fuel particles are used as the auxiliary fuel. By ejecting the solid fuel particles from the solid fuel nozzle 4 into the biomass fuel nozzle 3, the biomass fuel nozzle The ratio of the solid fuel particles on the inner wall side 3 increases.

  The biomass fuel in the biomass fuel nozzle 3 is narrowed by the concentrator 9 on the inner wall side of the biomass fuel nozzle 3 by the concentrator 9, so that the biomass fuel concentration along the radial inner wall of the biomass fuel nozzle 3 increases. By supplying solid fuel particles from the outer wall of the biomass fuel nozzle 3 to the region where the biomass fuel concentration is high, the solid fuel particles efficiently contact and mix with the biomass fuel.

And since the solid-gas two-phase flow in which the particle | grain density | concentration of biomass fuel and solid fuel increased along the radial inner wall of the biomass fuel nozzle 3 is formed, the ignitability of the fuel in the opening part of the furnace 12 improves. Furthermore, a flame holder 13 is installed on the outlet inner wall of the biomass fuel nozzle 3, and if a hole 10 through which solid fuel particles are ejected is provided in the vicinity of the flame holder 13, the solid fuel is placed in the vicinity of the flame holder 13. Since the particles are supplied, the particles are concentrated in the vicinity of the flame holder 13, and the particles are ignited, thereby enabling stable ignition of the fuel. Therefore, even when a biomass fuel having a relatively large particle size and a small proportion of fine particles is used, a decrease in ignitability during combustion is prevented, and stable combustion in the biomass combustion burner 1 is possible. For example, solid fuel particles Is fine particles of several tens of μm or less, and specifically, the solid fuel is finely pulverized and adjusted so that the ratio of particles having a size of 75 μm or less is 70% or more (about 70 to 90%). In this specification, pulverization to this extent is referred to as fine pulverization.
This corresponds to a particle size of pulverized coal that is suitable when pulverized coal is used as fuel in a coal-fired boiler. Moreover, although it will not ask | require a kind if it is a solid fuel, in order to improve ignitability, it is preferable to use solid fuel (for example, semi-carbonized biomass fuel) with a large amount of contained volatile matter.

  Moreover, if the boiler to operate | use is a mixed-fired boiler of pulverized coal and biomass fuel, it is preferable to use pulverized coal as solid fuel particles. In a co-fired boiler of pulverized coal and biomass fuel, the fuel supply system becomes more complicated when pulverized coal used for co-firing is used as a solid fuel than when other fuels such as semi-carbonized biomass fuel are newly prepared. No need.

As the biomass fuel, in addition to a typical woody biomass fuel, any plant-derived solid fuel may be used. Agricultural products such as corn and food waste such as tea leaves and coffee grounds may be used.
Biomass fuel does not need to be finely pulverized, but only coarsely pulverized (several millimeters or less, about 10% with a 200 mesh pass). Further, pulverization to this extent is referred to as coarse pulverization in this specification.

  Moreover, the hole 10 which is a jet port of solid fuel is good to be installed so that it may be ejected in the direction orthogonal to the fuel conveyance direction (direction along the central axis C) in the biomass fuel nozzle 3. When the solid fuel particulates are ejected in the same direction as the fuel conveyance direction in the biomass fuel nozzle 3, the solid fuel particulates exit the biomass combustion burner 1 along the flow, and mixing of the solid fuel particulates and the biomass fuel is performed. Not promoted.

  In solid combustion, fine particles of several tens of μm or less are ignited, and the propagation of flames starting from these fine particles causes combustion of fuel particles with a larger particle size. Is better promoted.

  Therefore, for example, as shown in FIG. 1, when the installation portion of the hole 10 that is the jet port of the solid fuel is formed so as to protrude from the wall surface of the biomass fuel nozzle 3 into the biomass fuel nozzle 3, Since the solid fuel particulates are ejected in the direction perpendicular to each other and the mixing of the solid fuel particulates and the biomass fuel is promoted, the ignitability of the combustion burner 1 is further prevented from being lowered, and stable combustion in the biomass combustion burner 1 is achieved. It becomes possible.

  Further, the fine particles of the solid fuel ejected from the hole 10 collide with the inner surface of the flame holder 13 (the rear surface when viewed from the furnace 12 side), and after the particle velocity is reduced, ignite near the biomass combustion burner 1. . Thus, since the fine particles are concentrated in the vicinity of the flame holder 13 installed on the outlet inner wall of the biomass fuel nozzle 3, the fine particles are ignited, and the fuel can be stably ignited.

FIG. 3 shows the shape of the flame holder 13 when viewed from the furnace 12 side toward the biomass combustion burner 1.
The flame holder 13 has a shark tooth shape, and in order to make the fine particles ejected from the hole 10 collide with the flame holder 13 effectively, the hole 10 is formed on the upstream side of the protrusion 13 a of the flame holder 13. It is preferable to install. By intensively ejecting the solid fuel fine particles to the protruding portion 13a, the ignitability can be improved even if the flow rate of the solid fuel is reduced as much as possible. Furthermore, although the shape of the hole 10 is shown as a circle in FIG. 2, the shape may be any of a circle or a polygon.

On the other hand, if the boiler to be operated is a biomass-fired boiler, the biomass fuel can be used more effectively. The finely pulverized biomass fuel is supplied to the solid fuel nozzle 4, and the coarsely pulverized biomass fuel is supplied to the biomass fuel nozzle 3.
In this case, even if the solid fuel of the finely pulverized biomass is reduced as much as described above, the ignitability is not lowered, so that an increase in power consumption for fine pulverization can be suppressed.

  Thus, finely pulverized biomass fuel can be used as solid fuel particles, but it is particularly preferable to use semi-carbonized biomass fuel that has been semi-carbonized as solid fuel particles. When the solid fuel biomass fuel is semi-carbonized, pyrolysis of the fibers in the biomass fuel occurs and the biomass fuel is easily pulverized. Furthermore, since the biomass fuel originally contains a large amount of volatile components and has high ignitability, it is a suitable fuel as solid fuel particles.

  In addition, when the fuel is finely pulverized, the power is reduced as compared with the untreated biomass fuel. By using a biomass fuel that has been semi-carbonized as a solid fuel, it is possible to provide a burner that does not require much labor for pulverization and has excellent ignitability. Moreover, it is preferable that the particle size of a semi-carbonized biomass fuel is 70% or more by a 200 mesh pass similarly to the case of fine pulverization of coal.

  It goes without saying that even when a biomass fuel that has not been carbonized at all is used as the biomass fuel supplied to the biomass fuel nozzle 3, effects such as prevention of a decrease in ignitability during combustion and stable combustion in the biomass combustion burner 1 are exhibited.

  FIG. 4 shows a system diagram of a biomass combustion apparatus provided with the biomass combustion burner 1 of FIG. The biomass combustion apparatus of the present embodiment includes a biomass bunker 16 that stores biomass fuel to be supplied to the biomass fuel nozzle 3, a biomass fuel supply machine 15 that supplies a certain amount of biomass fuel in the biomass bunker 16, and a biomass fuel supply machine In order to supply the biomass fuel pulverizer 14 for pulverizing the biomass fuel supplied by 15, the biomass fuel line 27 for supplying the biomass fuel pulverized by the biomass fuel pulverizer 14 to the biomass fuel nozzle 3, and the solid fuel nozzle 4 A solid fuel bunker 19 for storing the solid fuel, a solid fuel supply device 18 for supplying a certain amount of solid fuel in the solid fuel bunker 19, and a solid fuel pulverization for finely pulverizing the solid fuel supplied by the solid fuel supply device 18 Machine 20 and solid fuel crushed by solid fuel crusher 20 A solid fuel supply line 28 for supplying to the body fuel nozzle 4, and biomass combustion burner 1, and the like the furnace 12 burner 1 is installed.

Note that the combustion exhaust gas that has exited the furnace 12 is supplied from the exhaust gas line 29 to the exhaust gas treatment device 30 to be purified. Alternatively, a two-stage combustion apparatus may be used in which the combustion gas is supplied from the two-stage combustion gas supply line 22 to the two-stage combustion gas inlet 21 and supplied to the furnace 12.
The solid fuel is finely pulverized by the solid fuel pulverizer 20 and then supplied from the solid fuel supply line 28 to the solid fuel nozzle 4, and the biomass fuel is coarsely pulverized by the biomass fuel pulverizer 14 and then biomass from the biomass fuel line 27. It is supplied to the fuel nozzle 3.

  By providing the biomass fuel pulverizer 14 and the solid fuel pulverizer 20, the fuel can be smoothly supplied to the biomass fuel nozzle 3 and the solid fuel nozzle 4 after being pulverized.

  In particular, when remodeling or applying an existing coal-fired boiler to a co-fired boiler of pulverized coal and biomass fuel, it is preferable to use finely pulverized coal as the solid fuel, and to the solid fuel particle supply system It is preferable to use an existing coal bunker, coal feeder, and coal grinder.

  Therefore, since the biomass burning apparatus of the present embodiment makes it possible to use an existing coal-fired boiler as a pulverized coal combustion apparatus, the versatility of the existing coal-fired boiler is increased and it is economical.

FIG. 5 shows a system diagram (another example) of a biomass combustion apparatus provided with the biomass combustion burner 1 of FIG. A part of the description of the members having the same numbers as in FIG. 4 is omitted.
The biomass combustion apparatus of the present embodiment includes a biomass bunker 16 that stores biomass fuel to be supplied to the biomass fuel nozzle 3, a biomass fuel supply machine 15 that supplies a certain amount of biomass fuel in the biomass bunker 16, and a biomass fuel supply machine In order to supply the biomass fuel pulverizer 14 for pulverizing the biomass fuel supplied by 15, the biomass fuel line 27 for supplying the biomass fuel pulverized by the biomass fuel pulverizer 14 to the biomass fuel nozzle 3, and the solid fuel nozzle 4 The solid fuel reservoir 25 for storing the finely pulverized solid fuel, the solid fuel supply device 26 for supplying a certain amount of the solid fuel in the solid fuel reservoir 25, and the solid fuel supplied by the solid fuel supply device 26 Solid fuel supply line 28 that supplies the solid fuel nozzle 4 and biomass fuel A burner 1, and the like furnace 12 the burner 1 is installed.

  The solid fuel has already been finely pulverized and is stored in the solid fuel reservoir 25 in this state. The solid fuel reservoir 25 for storing the solid fuel may be a simple one such as a tank or a bottle. By providing the biomass fuel pulverizer 14 and the solid fuel reservoir 25, the fuel can be smoothly supplied to the biomass fuel nozzle 3 and the solid fuel nozzle 4.

  The biomass combustion apparatus shown in FIG. 5 differs from the biomass combustion apparatus shown in FIG. 4 in that a solid fuel composed of a bunker 19, a solid fuel supply machine 18, and a solid fuel crusher 20 connected to a solid fuel supply line 28. The supply system is composed of a solid fuel reservoir 25 that stores finely pulverized solid fuel and a solid fuel supply device 26 that supplies the solid fuel in the solid fuel reservoir 25 to the solid fuel supply line 28.

  In particular, in a biomass-fired boiler that does not use an existing coal-fired boiler, it is preferable to use a solid fuel supply system as a supply system using the solid fuel reservoir 25 and use semi-carbonized biomass as the solid fuel. If the semi-carbonized biomass fuel is left in the atmosphere for a long time, it absorbs moisture in the atmosphere and the grindability is lowered. In addition, a new semi-carbonized biomass fuel grinder is costly. However, by pulverizing and storing the semi-carbonized biomass fuel in the solid fuel reservoir 25 before absorbing moisture in the atmosphere, a simple combustion system can be constructed without requiring a large facility.

  According to the present invention, there is a possibility of use in a combustion burner or a combustion apparatus that uses solid fuel particles other than pulverized coal and biomass fuel.

DESCRIPTION OF SYMBOLS 1 Biomass combustion burner 2 Liquid fuel nozzle 3 Biomass fuel nozzle 4 Solid fuel nozzle 5 Combustion gas ejection nozzle 6 Air register 7 Combustion gas ejection nozzle (third order) 8 Venturi 9 Concentrator 10 Hole 12 Furnace 13 Flame holder 14 Biomass Fuel crusher 15 Biomass fuel supply machine 16 Biomass bunker 18 Solid fuel supply machine 19 Solid fuel bunker 20 Solid fuel crusher 21 Gas inlet for two-stage combustion 22 Gas supply line for two-stage combustion 25 Solid fuel reservoir 26 Solid fuel supply 27 Biomass fuel line 28 Solid fuel supply line 29 Exhaust gas line 30 Exhaust gas treatment device

Claims (4)

A liquid fuel nozzle provided on the central axis;
A biomass fuel nozzle that is provided on an outer periphery of the liquid fuel nozzle and conveys and ejects the biomass fuel and the carrier gas;
A fuel concentrator which is provided on the outer periphery of the liquid fuel nozzle and narrows the flow path of the fuel in the biomass fuel nozzle to the inner wall side of the biomass fuel nozzle;
A flame holder provided on the inner wall of the tip of the biomass fuel nozzle;
A biomass combustion burner provided on the outer periphery of a biomass fuel nozzle and provided with a combustion gas nozzle for ejecting a combustion gas of fuel,
A solid fuel nozzle is provided on the outer periphery of the biomass fuel nozzle and on the inner periphery of the combustion gas nozzle to convey solid fuel particles and eject the particles into the biomass fuel nozzle,
A biomass combustion burner characterized in that the jet port of the solid fuel transfer nozzle is provided between the fuel concentrator and the flame holder and on the wall of the biomass fuel nozzle near the flame holder.   The biomass combustion burner according to claim 1, wherein the solid fuel is a semi-carbonized biomass fuel. The biomass burning burner according to claim 1, wherein the solid fuel particles are pulverized coal;
A biomass combustion apparatus comprising: a solid fuel pulverizer that pulverizes solid fuel supplied to the solid fuel nozzle into particles. A biomass burning burner according to claim 2;
A biomass combustion apparatus comprising: a solid fuel reservoir that stores particles of biomass fuel that has been semi-carbonized to be supplied to the solid fuel nozzle.

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